Developing the robot emotion engine

Now we are going to put together the robot’s emotion model. This is the heart of the artificial personality as it computes, updates, and remembers the emotional state of the robot. The robot starts in a generally neutral state and performs updates based on the combination of eight emotional traits: happy/sad, welcoming/distant, friendly/ stranger, curious/frustrated, and fresh/tired. As events happen in the experience of the robot, it gets cues that cause its emotional state to change. For example, if the user said “That is stupid” to something the robot said, then the robot would add to the sad axis of its emotion.

We compute the overall emotional state using polar coordinates, just like you saw in the diagram we drew earlier in this chapter (Figure 9.4). The current emotional state is determined by computing the center of mass of the other emotions. If the emotions are more or less balanced, the center of mass of the emotions...